Vascular, Soft Tissue, and Musculoskeletal Imaging in Systemic Sclerosis

This review examines the role of various imaging techniques in assessing vascular and musculoskeletal manifestations in Systemic Sclerosis (SSc). Imaging modalities, such as thermography, capillaroscopy, ultrasound, optical coherence tomography, laser speckle contrast analysis, radiography, computed tomography, and MRI, offer valuable insights into SSc-related complications. Findings suggest that these techniques aid in diagnosing conditions like Raynaud phenomenon, digital ulcers, calcinosis, acro-osteolysis, and hand contractures. However, each modality has its advantages and limitations, necessitating a multimodal approach for comprehensive evaluation and accurate diagnosis of SSc-related manifestations.

GPER Acts Through the cAMP/Epac/JNK/AP-1 Pathway to Induce Transcription of Alpha 2C Adrenoceptor in Human Microvascular Smooth Muscle Cells

ABSTRACT

Raynaud's phenomenon, which results from exaggerated cold-induced vasoconstriction, is more prevalent in females than males. We previously showed that estrogen increases the expression of alpha 2C-adrenoceptors (α 2C -AR), the sole mediator of cold-induced vasoconstriction. This effect of estrogen is reproduced by the cell-impermeable form of the hormone (E 2 :bovine serum albumin [BSA]), suggesting a role of the membrane estrogen receptor, G-protein-coupled estrogen receptor [GPER], in E 2 -induced α 2C -AR expression. We also previously reported that E 2 upregulates α 2C -AR in microvascular smooth muscle cells (VSMCs) via the cAMP/Epac/Rap/JNK/AP-1 pathway, and that E 2 :BSA elevates cAMP levels. We, therefore, hypothesized that E 2 uses GPER to upregulate α 2C -AR through the cAMP/Epac/JNK/AP-1 pathway. Our results show that G15, a selective GPER antagonist, attenuates the E 2 -induced increase in α 2C -AR transcription. G-1, a selective GPER agonist, induced α 2C -AR transcription, which was concomitant with elevated cAMP levels and JNK activation. Pretreatment with ESI09, an Epac inhibitor, abolished G-1-induced α 2C -AR upregulation and JNK activation. Moreover, pretreatment with SP600125, a JNK-specific inhibitor, but not H89, a PKA-specific inhibitor, abolished G-1-induced α 2C -AR upregulation. In addition, transient transfection of an Epac dominant negative mutant (Epac-DN) attenuated G-1-induced activation of the α 2C -AR promoter. This inhibitory effect of Epac-DN on the α 2C -AR promoter was overridden by the cotransfection of constitutively active JNK mutant. Furthermore, mutation of AP-1 site in the α 2C -AR promoter abrogated G1-induced expression. Collectively, these results indicate that GPER upregulates α 2C -AR through the cAMP/EPAC/JNK/AP-1 pathway. These findings unravel GPER as a new mediator of cold-induced vasoconstriction, and present it as a potential target for treating Raynaud's phenomenon in estrogen-replete females.

Peculiarities of Adverse Events Manifested by Injury of Skin and Skin Derivatives and Associated with Beta-blockers Use

More than 50 years after Propranolol was introduced to the pharmaceutical market as a drug that can lower the heart rate, beta-blockers (BAB) are still widely used in the pharmacotherapy of cardiovascular diseases. However, the use of BAB has a number of limitations, first of all, due to adverse drug events (AE) that develop during their use. The purpose of our review was to study the features of the BAB AE manifested by injuries of the skin and its appendages. The clinical manifestations of them are the development or exacerbation of psoriasis, lichen planus, contact dermatitis, acrocyanosis, Raynaud's disease, alopecia, hyperhidrosis, vitiligo, anaphylaxis, and allergic skin reactions. True medicinal psoriasis occurs in patients taking BAB with no family or previous history and most often mimics erythrodermic psoriasis and palmar-plantar pustular psoriasis. Systemic use of BAB can also be accompanied by exacerbation of vitiligo. In patients with segmental vitiligo, the results of Doppler flowmetry and iontophoresis showed increased blood flow in vitiligo foci compared with normal skin. The development of anaphylactic reactions against the background of BAB therapy may be due to the modulation of adenylate cyclase, which can affect the release of anaphylactogenic mediators, as well as a decrease in the severity of cardiovascular compensatory changes. The peculiarities of the development of such reactions may be the resistance of patients to traditional treatment, which is due to the development of paradoxical reflex vagotonic effects when using adrenaline. Some of the mentioned AE may pose a potential threat to the life and health of the patient and therefore require additional discussion.

Raynaud's Phenomenon: A Brief Review of the Underlying Mechanisms

Raynaud’s phenomenon (RP) is characterized by exaggerated cold-induced vasoconstriction. This augmented vasoconstriction occurs by virtue of a reflex response to cooling via the sympathetic nervous system as well as by local activation of α_2C adrenoceptors (α_2C-AR). In a cold-initiated, mitochondrion-mediated mechanism involving reactive oxygen species and the Rho/ROCK pathway, cytoskeletal rearrangement in vascular smooth muscle cells orchestrates the translocation of α_2C-AR to the cell membrane, where this receptor readily interacts with its ligand. Different parameters are involved in this spatial and functional rescue of α_2C-AR. Of notable relevance is the female hormone, 17β-estradiol, or estrogen. This is consistent with the high prevalence of RP in premenopausal women compared to age-matched males. In addition to dissecting the role of these various players, the contribution of pollution as well as genetic background to the onset and prevalence of RP are also discussed. Different therapeutic approaches employed as treatment modalities for this disease are also highlighted and analyzed. The lack of an appropriate animal model for RP mandates that more efforts be undertaken in order to better understand and eventually treat this disease. Although several lines of treatment are utilized, it is important to note that precaution is often effective in reducing severity or frequency of RP attacks.